Bag, composite material, and method of making



March so, 1943. E. D. GREENE 2,314,876

BAG, COMPOSITE MATERIAL AND METHOD OF MAKING Filed Feb. 9, 1939'nmlmmwwmnl I '(1 lllIlllIIAlHtulI-IIIIIIM INVENTOR Eownv D. GREENE a wS ATTORNEYD' Patented Mar. 30, i

BAG, COMPOSITE MATERIAL, AND METHOD OF MAKING Edwin D. Greene, New York,N. Y., assignor to Arkell Safety Bag Company, New York, N. Y acorporation of New York Application February 9, 1939, Scrial'No. 255,467

(Cl. 15H") 8 Claims.

In packaging finely divided material such as sugar, cement and chemicalsin approximately one hundred pound lots, cloth bags, paper-lined clothbags or multi-wall plain paper bags have heretofore been generallyemployed. Such bags, however, have certain disadvantages.

Cloth bags, and paper-lined cloth bags are expensive. In the .case ofmulti-wall plain paper bags, owing to the unstretchability of the plainpaper used and the difilculty in evenly laying the plies in closecontact with each other, the plies do not uniformly resist burstingstrains. Moreover the stiffness of the multi-ply walls causes them toeasily buckle and break when in use.

One of the objects of the present invention is to provide a bag whichovercomes the disadvantages of the bags heretofore produced as abovedescribed.

Another object of the invention is to providenovel and improvedcomposite sheet material and method of forming the same.

The several features of the invention, whereby the above-mentioned andother objects may be attained, will be readily understood from thefollowing description and accompanying drawing, in which:

Figure l is a plan view of my improved composite material in itspreferred form;

Fig. 2 is a longitudinal sectional view, partly diagrammatical and on anenlarged scale, of the same;

Fig. 3 is a similar view of a modified form;

Fig. 4 is a side elevation of my improved bag in its preferred form;

Fig. 5 is a transverse sectional view, partly cliagrammatical, taken onthe line 5-5 of Fig. 4; and

Fig. 6 is a detail transverse sectional view, on an enlarged scale ofthe side seam of the bag.

My improved composite material is preferably made up of three webs orsheets 2, 3 and 4 of crinkled paper arranged in superposed relation.Preferably the crinkles extend generally transversely of the sheets andthe three sheets are of substantially the same stretchability. Thedegree of stretchability may be varied but, in making bags of thematerial, I have obtained the most satisfactory results with crinkledpaper having approximately fifteen per centum of stretchability.Preferably the several plies are of uniform stretchability but owing tothe manner in which they are secured together as hereinafter described,any slight variation in the stretchability does not materially aifectthe strength of the composite material, and in cases where the materialhas been made into bags, I have had satisfactory results even when theintermediate sheet has had substantially more stretch than the othersheets.

The crinkles preferably are formed by the water-creped method whichconsists in passing each sheet to be crinkled through a water bath to acrinkling cylinder where it is removed by means of a doctor blade. Bycrinkling the sheets by this method, it has been found that they havemaximum elasticity. In the case of my product, I have i had verysatisfactory results with relatively fine crinkles formed in the paper.

When the three sheets are thus crinkled, a thin coating of suitableadhesive substance 8, such as latex or asphalt, preferably the latter,is applied to the crests of the crinkles on one side of each of thesheets 2 and 4, as illustrated in Fig. 2. Such application of asphaltmay be performed in any suitable manner as by running the sheets over arotating cylinder bearing a thin coating of heated asphalt.

When the crests of the crinkles on one side of each of the two sheets 2and 4 has the asphalt thus applied, while the asphalt is in moistcondition the coated sides of the two sheets are applied to the oppositesides of the intermediate sheet 3 and suflicient pressure is applied tothe three sheets to cause the crests of the crinkles of the outer sheetsto be secured to the intermediate sheet.

With the three sheets thus secured together in accordance with myimproved method, I have found that there is no substantial nesting ofthe crinkles and only the crests of the crinkles of th three sheets aresecured together. Moreover portions of the crests of substantially allof the crinkles of the inner sides of the outer sheets are secured toportions of the crests of substantially all of the crinkles of theintermediate sheet 3. The valleys between the crests remain unsecuredand, consequently, closely spaced dead air spaces or pockets areprovided between the sheets. Crinkled paper made by the water-crepemethod have the crests of the crinkles all substantially in the sameplane, and the individual crinkles are made up of portions that are moreor less angu larly arranged in uneven lines. It is principally becauseof such formation of the crinkles that there is no substantial nestingof the crinkles of adjacent sheets while the sheets are being securedtogether as above described.

I have found that by thus securing the sheets together that theresistance to a stretching strain of the composite sheet is materiallyincreased without materially impairing the resiliency of the sheets.

While my composite material may be used for various purposes, I find itparticularly advantageous for making bags, especially large bags forholding as much as one hundred pounds or even more of finely dividedmaterial. Where the composite material is to be used for this purpose,the sheets 2, 3 and l of crinkled, paper are preferably applied inoverlapping relation as shown in Fig. 1.

To form the bag as illustrated in Fig. 4, a sheet of the compositematerial of the desired length may be cut from the web and the sheetmade into tubular form as shown. To form the back seam 9 the overlappingedges of the composite sheet may be secured together by latex, or othersuitable adhesive, as shown in Fig. 6, so that the corresponding marginsof all three sheets are secured to the other corresponding margins ofthe sheets.

If desired "bellows folds It may be provided in the sides of the tube,and one end of th tube closed in any suitable manner as by means of afolded and sewn seam l2. The other end of the tube may be left open,prior to filling, or if desired may be closed and a filling valve formedtherein.

I have found that my improved bag when filled, is extremely strongcircumferentially as well as longitudinally, and will withstand roughhandling and bursting strains to a much greater degree than multiplyplain paper bags of the same basis weight of paper. Also, even aftersevere tests there is very little lengthening and the bag as a wholekeeps its shape remarkably well. The walls of the bag do not tend tobuckle and have cloth-like flexibility. Because of the strength andpliability of the bag, it may be re-used for certain purposes and mayhave more resale value than plain paper bags.

Moreover, the bag efl'ectively resists the admission of air and moistureand has high heatinsulating qualities, this probably being due to thedead air spaces or pockets between the crinkles of adjacent sheets. Onereason for the extreme pliability and strength of the material, isapparently due to the manner in which the piles are yieldingly securedtogether at the crests of the crinkles which allows slight relativemovement of the plies, and the plies are more or less cushioned by theair pockets between them.

If desired to increase the air and moistureproofness, all three pliesmay be treated with waterproofing material.

To provide the most effective air'and moistureprooi' bag, I preferablymake the intermediate ply of two layers of paper ll which previously tocrinkling are secured together in superposed relation by means of alayer of asphalt or other waterproofing substance. Also, if desired theouter plies of the composite material may be treated with a suitablewaterproofing material.

I have secured the best results and maximum strength for the amount ofpaper used with the use of three plies of paper, the intermediate plyapparently serving most efiiciently to cushion and reinforce the otherplies. If desired, however, the number of plies may be increased, and insome instances only two plies may be used. In

, making composite material of two plies, either the ply 2 or 4 may beomitted, and in forming two-ply bags the inner ply may be omitted.

As will be evident to those skilled in the art, my invention permitsvarious modifications without departing from the spirit thereof or thescope of the appended claims.

What I claim is:

1. A bag made of composit material of the class described comprising aplurality of sheets of crinkled paper arranged in superposed relationwith the crests of the crinkles of adjacent sides of adjacent sheetsarranged generally in juxtaposition and adhesively secured togethersubstantially throughout the areas of the sheets. the crinkles ofadjacent sheets being generally in non-nested relation and thesuperposedvalleys of the crinkles of said sheets opening into one another andforming air spaces between the sheets, the crinkles in all of the sheetsextending transversely of the bag to provide elastic stretcha bilitylongitudinally of the bag.

2. A bag made of composite material of the class described comprising atleast three sheets of crinkled paper arranged in superposed relationwith the crests of the crinkles of adjacent sides of adjacent sheetsarranged generally in juxtaposition and adhesively secured togethersubstantially throughout the areas of the sheets, the crinkles ofadjacent sheets being generally in nonnested relation and the superposedvalleys of the crinkles of said sheets opening into one another andforming air spaces between the sheets, the crinkles in all of the sheetsextending transversely of the bag to provide for elastic stretchabilitylongitudinally of the bag, the bag being substantially non-elasticallystretchable circumierentially thereof.

3. A structure according to claim 2 in which an intermediate sheetcomprises two plies that are crinkled together and are also securedtogether by means of a waterproof adhesive so as to form a two-plywaterproof sheet.

4. Composite material of the class described comprising a plurality ofwebs of crinkled paper arranged in superposed relation with the crestsof the crinkles of adjacent sides of adjacent webs arranged generally injuxtaposition and secured together by means of asphaltic adhesivesubstantially throughout the areas of the webs, the crinkles of adjacentwebs being generally in nonnested relation and the superposed valleys ofthe crinkles of said webs opening into one another and forming airspaces between the webs, the crinkles in all of the webs extendingtransversely of the composite material to provide for elasticstretchability longitudinally of the material, said superposed valleysbeing substantially free of the adhesive.

5. Composite material of th class described comprising at least threewebs of crinkled paper arranged in superposed relation with the crestsof the crinkles of adjacent sides of adjacent webs arranged generally injuxtaposition and secured together substantially throughout the areas ofthe webs, the crinkles of adjacent webs being generally in non-nestedrelation and thesuperposed valleys of the crinkles of said webs openinginto one another and forming air spaces between the webs, the crinklesin all of the webs extending trans versely of the composite material toprovide for elastic stretchability longitudinally of the material.

6. A structure according to claim 5 in which an intermediate webcomprises two plies that are crinkled together and are also securedtogether by means of a waterproof adhesive so as to form a two-plywaterproof web.

7. The method of forming composite material of at least three webs ofcrinkled paper having .heir crinkles extending transversely of the webs,vhich comprises applying adhesive material to he crests of the crinkleson one side of each of we of the webs, and superposing said webs on)pposite sides of a third web so as to cause said zdhesive to securesaid crests of the inner sides )f the first two webs to the sides of theinternediate web, whereby the crinkles of adjacent webs are arrangedgenerally in non-nested relation and the superposed valleys of thecrinkles open into one another and form air spaces between the webs, thecrests of the crinkles of adjacent sides of adiacent webs being arrangedgenerally in juxtaposition substantially throughout the areas of thewebs.

8. A bag made of composite material of the class described comprising atleast three sheets of crinkled paper arranged in superposed relationwith the crinkles arranged generally in nonnested condition, asphalticadhesive securing the superposed crests of the crinkles of adjacentsheets together, said crests being arranged generally in juxtapositionthroughout the areas of the sheets, the superposed valleys of thecrinkles of said sheets opening into one another and forming air spacesbetween the sheets, said valleys being substantially free of saidasphaltic adhesive, and the crinkles in all of the sheets extendingtransversely of the bag to provide elastic stretchability longitudinallyof the bag.

EDWIN D. GREENE.

